package roomescape.payment.service;

import java.time.OffsetDateTime;
import java.util.Optional;

import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import roomescape.common.exception.ErrorType;
import roomescape.common.exception.RoomescapeException;
import roomescape.payment.domain.CanceledPayment;
import roomescape.payment.domain.Payment;
import roomescape.payment.domain.repository.CanceledPaymentRepository;
import roomescape.payment.domain.repository.PaymentRepository;
import roomescape.payment.dto.request.PaymentCancelRequest;
import roomescape.payment.dto.response.PaymentCancelResponse;
import roomescape.payment.dto.response.PaymentResponse;
import roomescape.payment.dto.response.ReservationPaymentResponse;
import roomescape.reservation.domain.Reservation;

@Service
@Transactional
public class PaymentService {

	private final PaymentRepository paymentRepository;
	private final CanceledPaymentRepository canceledPaymentRepository;

	public PaymentService(PaymentRepository paymentRepository, CanceledPaymentRepository canceledPaymentRepository) {
		this.paymentRepository = paymentRepository;
		this.canceledPaymentRepository = canceledPaymentRepository;
	}

	public ReservationPaymentResponse savePayment(PaymentResponse paymentResponse, Reservation reservation) {
		Payment payment = new Payment(paymentResponse.orderId(), paymentResponse.paymentKey(),
			paymentResponse.totalAmount(), reservation, paymentResponse.approvedAt());
		Payment saved = paymentRepository.save(payment);
		return ReservationPaymentResponse.from(saved);
	}

	@Transactional(readOnly = true)
	public Optional<Payment> findPaymentByReservationId(Long reservationId) {
		return paymentRepository.findByReservationId(reservationId);
	}

	public void saveCanceledPayment(PaymentCancelResponse cancelInfo, OffsetDateTime approvedAt, String paymentKey) {
		canceledPaymentRepository.save(new CanceledPayment(
			paymentKey, cancelInfo.cancelReason(), cancelInfo.cancelAmount(), approvedAt, cancelInfo.canceledAt()));
	}

	public PaymentCancelRequest cancelPaymentByAdmin(Long reservationId) {
		String paymentKey = findPaymentByReservationId(reservationId)
			.orElseThrow(() -> new RoomescapeException(ErrorType.PAYMENT_NOT_POUND,
				String.format("[reservationId: %d]", reservationId), HttpStatus.NOT_FOUND))
			.getPaymentKey();
		// 취소 시간은 현재 시간으로 일단 생성한 뒤, 결제 취소 완료 후 해당 시간으로 변경합니다.
		CanceledPayment canceled = cancelPayment(paymentKey, "고객 요청", OffsetDateTime.now());

		return new PaymentCancelRequest(paymentKey, canceled.getCancelAmount(), canceled.getCancelReason());
	}

	private CanceledPayment cancelPayment(String paymentKey, String cancelReason, OffsetDateTime canceledAt) {
		Payment payment = paymentRepository.findByPaymentKey(paymentKey)
			.orElseThrow(() -> throwPaymentNotFoundByPaymentKey(paymentKey));
		paymentRepository.delete(payment);

		return canceledPaymentRepository.save(new CanceledPayment(paymentKey, cancelReason, payment.getTotalAmount(),
			payment.getApprovedAt(), canceledAt));
	}

	public void updateCanceledTime(String paymentKey, OffsetDateTime canceledAt) {
		CanceledPayment canceledPayment = canceledPaymentRepository.findByPaymentKey(paymentKey)
			.orElseThrow(() -> throwPaymentNotFoundByPaymentKey(paymentKey));
		canceledPayment.setCanceledAt(canceledAt);
	}

	private RoomescapeException throwPaymentNotFoundByPaymentKey(String paymentKey) {
		return new RoomescapeException(
			ErrorType.PAYMENT_NOT_POUND, String.format("[paymentKey: %s]", paymentKey),
			HttpStatus.NOT_FOUND);
	}
}